Keywords:

Wind: moving air
Air Pressure: Force applied by air.
Land Breeze: cool air rushes from the land towards the sea at night
Sea Breeze: cool air from the sea  rushes towards the land during the day

Introduction

Riddle:

It is present all around us. It is even present in this room with us right now! But we cannot see it. What is it that I’m talking about?

Answer: The answer is Air! Air is all around us. Even in this room where we are sitting, the air is present with us.
Can we see the air? No! Can we hear it? No! Can we taste the air? No! Can we smell it? No, unless there’s some fragrance in the air, for example, perfume! Or stench (bad smell), that is when the air smells bad! Can we feel the air? No! If you can feel it, that means the air is moving, which we call  wind!”

What is wind?

The wind is air in motion. When air moves from one place to another, the wind is formed. You must have all experienced a windy day! Strong winds blow from one place to another!  The wind has a speed and a direction.

If we cannot see the wind, how do we know that it moves?

We know about the movement of wind by understanding the movement of objects on which the wind exerts its force.  We observe different effects of the wind which tells us the direction in which the wind is moving.

Light winds such as a cool breeze can have a calming effect on us but strong winds do not!  We can feel the wind’s movement on our bodies. We can tell if it is a light breeze or a strong gush of wind.

The flow of wind through our hair makes it fly. Wind can put off a candle flame or a small fire.

The force of wind carries things with it. The movement of dust particles through the air lets us know that wind is moving. The force of a strong wind can make a pile of newspapers fly!

During monsoons, it becomes difficult to walk with an umbrella when there are strong winds as the umbrella gets pulled in the direction of the wind flow.

Extremely strong winds such as thunderstorms, tornadoes, and cyclones can tear apart the roof of a house and knock vehicles over! The wind is not good for us always, Mother Nature can be very angry indeed!

What does a ceiling fan do? You flip the fan switch on, the blades rotate so fast that they move the air and you can feel the cool wind from the fan!

How does nature create wind?

The wind is nothing but air in motion. What sets the wind in motion is the difference in the air pressures.  It is caused by the uneven heating of the Earth’s surface by the sun.
The reasons behind the uneven heating of Earth’s surface are cloud cover, mountains, valleys, water bodies, vegetation, desert lands, and different geographical locations on earth.

This uneven heating of the Earth’s surface causes the warm air present near the surface to rise, and cool air comes down, leading to the formation of high and low-pressure regions on the Earth.

Warm Air Rises!

As the air rises, the pressure in that region becomes less and this makes the surrounding region have an area of high pressure. The air from this high-pressure region now rushes in, leading to the formation of wind.

Unequal heating and cooling of land and sea cause breezes.

SEA BREEZE:  By day the land is warm and the sea cool. The warm air above the land rises and the cool air from the sea comes down and rushes towards the land. The breeze is from the sea.

LAND BREEZE:  At night the land is cool and the sea warm. The air above the sea rises and cool air rushes from the land towards the sea.